Copyright ©The Author(s) 2020.
World J Cardiol. Sep 26, 2020; 12(9): 437-449
Published online Sep 26, 2020. doi: 10.4330/wjc.v12.i9.437
Table 1 Physiological meaning and cut-off values of electrocardiogram -indices of ventricular repolarization
Repolarization heterogeneity aspectT-wave indexCut-off values (arrhythmogenesis)
Maximal end of repolarization/maximal APD valuesQT450 ms (males), 460 ms (females)[119]
Maximal end of repolarization/maximal APD values in conditions of QRS wideningJTend
The proportion between the minimal and the maximal APDTpeak-Tend/QT0.22[122]; 0.23[123]; 0.31[114]
T-wave symmetry≤ 1.7[98]
The global repolarization dispersionTpeak-Tend≥ 103.3 ± 17.4 ms[86,87]; ≥ 142 ms[114]
T-wave amplitude and T-wave area, calculated on the basis of T-vector or Root Mean Square ECG
Ventricular gradient, or QRS-T integral
Local differences in repolarization dispersionTpeak-Tend dispersion35 ms[113]; 42 ms[114]
Lead-to-lead differences in Tpeak and Tend instants between adjacent leads
Local differences in the end of repolarization timesQT dispersion39 ms[114]; 93 ms[124]
Early repolarization (plateau phase)JTpeak
The difference in the spatial sequence of depolarization and repolarizationSpatial QRS-T angle135°[89,94-99]
The general direction of repolarization sequenceT-vector projection onto the heart ventricles
T-loop complexity
The relative magnitudes of apicobasal, anterior-posterior and left-to-right repolarization gradientsRatio between X, Y, Z components of T-vector
The location or the areas of the shortest and the longest APDT-vector projection onto the heart ventricles
Electrical instability of ventricular myocardium at cellular levelMacrovolt and microvolt T-wave alternans
Beat-to-beat T-vector variability